Variable Automatic Gain Control Loop Gain Patents (Class 455/240.1)
  • Patent number: 11689309
    Abstract: An optical reception apparatus (1) of the present invention includes: a local oscillator (11) outputting local oscillation light (22); an optical mixer (12) receiving a multiplexed optical signal (21) and the local oscillation light, and selectively outputting an optical signal (23) corresponding to the wavelength of the local oscillation light from the multiplexed optical signal; a photoelectric converter (13) converting the optical signal (23) output from the optical mixer into an electric signal (24); a variable gain amplifier (15) amplifying the electric signal (24) to generate an output signal (25) whose output amplitude is amplified to a certain level; a gain control signal generating circuit (16) generating a gain control signal (26) for controlling the gain of the variable gain amplifier (15); and a monitor signal generating unit (17) generating a monitor signal (27) corresponding to the power of the optical signal (23) using the gain control signal (26).
    Type: Grant
    Filed: March 8, 2022
    Date of Patent: June 27, 2023
    Assignee: NEC CORPORATION
    Inventor: Yusuke Yamauchi
  • Patent number: 11646799
    Abstract: An optical data transmission system and method employs positive only data modulation, with an offset applied to the positive modulated values before generating modulated drive current signals for a light emitting component. The offset is such that the minimum drive current falls in a range where the electron-to-photon efficiency of the light emitting component is substantially constant. The drive current thus falls in a more linear part of its current vs. intensity characteristic. This reduces distortion and hence enables increased data rate.
    Type: Grant
    Filed: June 28, 2019
    Date of Patent: May 9, 2023
    Assignee: SIGNIFY HOLDING B.V.
    Inventor: Johan Paul Linnartz
  • Patent number: 11522737
    Abstract: Systems and methods for automatic level control (ALC) are provided. In one embodiment, an ALC system for communications signals comprises: a multi-threshold programmable ALC controller; and at least one signal path that includes: a digital step attenuator configured to receive an analog communications signal and attenuate the analog communications signal in response to an attenuation adjustment signal from the ALC controller; and an analog-to-digital converter configured to receive the analog communications signal as attenuated by the digital step attenuator and generate samples of the attenuated analog communications signal, wherein the ALC controller receives the samples. The ALC controller comprises a plurality of clip detectors that function in parallel. Each of the clip detectors are programmed with a respective amplitude and time threshold.
    Type: Grant
    Filed: April 29, 2021
    Date of Patent: December 6, 2022
    Assignee: CommScope LLC
    Inventors: Marco Parrucci, Enrico Maria Fabbri, Samuele Brighenti
  • Patent number: 11290202
    Abstract: An optical reception apparatus (1) of the present invention includes: a local oscillator (11) outputting local oscillation light (22); an optical mixer (12) receiving a multiplexed optical signal (21) and the local oscillation light, and selectively outputting an optical signal (23) corresponding to the wavelength of the local oscillation light from the multiplexed optical signal; a photoelectric converter (13) converting the optical signal (23) output from the optical mixer into an electric signal (24); a variable gain amplifier (15) amplifying the electric signal (24) to generate an output signal (25) whose output amplitude is amplified to a certain level; a gain control signal generating circuit (16) generating a gain control signal (26) for controlling the gain of the variable gain amplifier (15); and a monitor signal generating unit (17) generating a monitor signal (27) corresponding to the power of the optical signal (23) using the gain control signal (26).
    Type: Grant
    Filed: October 1, 2020
    Date of Patent: March 29, 2022
    Assignee: NEC CORPORATION
    Inventor: Yusuke Yamauchi
  • Patent number: 11146378
    Abstract: A signal receiving device may not need to consider jitter characteristics of a received signal by including a transition detecting device which receives first to third input signals having different signal levels for each unit interval, compares whether a signal level of a first differential signal, which is a differential signal between the first input signal and the second input signal among the first to third input signals, is greater than a first reference signal level to output a first comparison signal, and compares whether the signal level of the first differential signal is greater than a second reference signal level different from the first reference signal level to output a second comparison signal, and a clock data recovering device which recovers a clock signal embedded in the first to third input signals on the basis of the first and second comparison signals to output the recovery clock signal.
    Type: Grant
    Filed: June 1, 2020
    Date of Patent: October 12, 2021
    Assignees: SAMSUNG ELECTRONICS CO., LTD., RESEARCH & BUSINESS FOUNDATION SUNGKYUNKWAN UNIVERSITY
    Inventors: Tae-Jin Kim, Jung-Hoon Chun, Jae Youl Lee, Hyun Wook Lim
  • Patent number: 10826642
    Abstract: An optical reception apparatus (1) of the present invention includes: a local oscillator (11) outputting local oscillation light (22); an optical mixer (12) receiving a multiplexed optical signal (21) and the local oscillation light, and selectively outputting an optical signal (23) corresponding to the wavelength of the local oscillation light from the multiplexed optical signal; a photoelectric converter (13) converting the optical signal (23) output from the optical mixer into an electric signal (24); a variable gain amplifier (15) amplifying the electric signal (24) to generate an output signal (25) whose output amplitude is amplified to a certain level; a gain control signal generating circuit (16) generating a gain control signal (26) for controlling the gain of the variable gain amplifier (15); and a monitor signal generating unit (17) generating a monitor signal (27) corresponding to the power of the optical signal (23) using the gain control signal (26).
    Type: Grant
    Filed: January 13, 2020
    Date of Patent: November 3, 2020
    Assignee: NEC Corporation
    Inventor: Yusuke Yamauchi
  • Patent number: 10374650
    Abstract: Apparatus and methods for filter bypass for radio frequency front-ends are provided. In certain configurations, a front-end system includes a low noise amplifier, a blocker filter, a plurality of switches configured to control connectivity of the blocker filter and the low noise amplifier in a signal path through the front-end system. The front-end system further includes a controller configured to control the plurality of switches to operate the front-end system in a selected mode chosen from a plurality of modes. The plurality of modes includes a first mode in which the blocker filter is before the low noise amplifier in the signal path, and a second mode in which the low noise amplifier is before the blocker filter in the signal path.
    Type: Grant
    Filed: September 14, 2018
    Date of Patent: August 6, 2019
    Assignee: Skyworks Solutions, Inc.
    Inventors: David Richard Pehlke, Stephane Richard Marie Wloczysiak
  • Patent number: 10230413
    Abstract: Filtering architectures and methods for wireless applications. In some embodiments, a wireless architecture can include a pre-amplifier filter configured to filter a signal, and an amplifier assembly configured to amplify the filtered signal. The wireless architecture can further include a filter circuit configured to provide selective filtering of the amplified signal based at least in part on a rejection level of the pre-amplifier filter and a gain of the amplifier assembly. In some embodiments, such a wireless architecture can be implemented in a packaged module or a wireless device.
    Type: Grant
    Filed: August 28, 2017
    Date of Patent: March 12, 2019
    Assignee: Skyworks Solutions, Inc.
    Inventors: Stephane Richard Marie Wloczysiak, Joel Richard King
  • Patent number: 10103772
    Abstract: Apparatus and methods for filter bypass for radio frequency front-ends are provided. In certain configurations, filter connectivity of a front-end is changed as a function of automatic gain control (AGC) in a receive path. For example, lossy filtering can be bypassed when signal conditions and the surrounding interference environment allow. In certain implementations, an additional gain state is added to the AGC in the form of a bypass of the filtering. Thus, receiver gain and noise figure are greatly improved while the linearity and susceptibility to blockers is degraded.
    Type: Grant
    Filed: August 8, 2017
    Date of Patent: October 16, 2018
    Assignee: Skyworks Solutions, Inc.
    Inventors: David Richard Pehlke, Stephane Richard Marie Wloczysiak
  • Patent number: 9270312
    Abstract: A signal reception apparatus in a communication system supporting a beam forming scheme is provided. The signal reception apparatus includes a Low Noise Amplifier (LNA) configured to generate a second signal by amplifying a first signal according to a first gain value, a Variable Gain Amplifier (VGA) configured to generate a third signal by amplifying the second signal according to a second gain value, and an Automatic Gain Controller (AGC) configured to control the first gain value and the second gain value by considering a plurality of beam types supported in a signal transmission apparatus.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: February 23, 2016
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jeong-Ho Park, Won-Suk Choi, Hyun-Kyu Yu, Jae-Weon Cho
  • Patent number: 9059665
    Abstract: Multi-output amplifiers with configurable source degeneration inductance and having good performance are disclosed. In an exemplary design, an apparatus (e.g., a wireless device or an integrated circuit) includes a gain transistor and a configurable degeneration inductor for an amplifier. The gain transistor receives an input signal and provides an amplified signal. The amplifier provides a single output signal in a first operating mode or a plurality of output signals in a second operating mode. The configurable degeneration inductor is coupled to the gain transistor and provides a first source degeneration inductance in the first operating mode or a second source degeneration inductance in the second operating mode. The second source degeneration inductance is less than the first source degeneration inductance and may be dependent on the number of output signals generated in the second operating mode.
    Type: Grant
    Filed: February 22, 2013
    Date of Patent: June 16, 2015
    Assignee: Qualcomm Incorporated
    Inventors: Ahmed A. Youssef, Li-Chung Chang
  • Patent number: 9002308
    Abstract: A system is disclosed that may include an Automatic Gain Control (AGC) module configured to automatically adjust the gain of a receiver, which is configured to receive a signal. The signal includes a number of commands, which have a characteristic command length and a characteristic command interval. The command length may have a substantially shorter duration than the command interval. The system may also include a slicer configured to interface to a command processor. The system includes a command processor communicatively coupled with the AGC module and/or the slicer for providing a notification to the AGC module and/or the slicer associated with the ends of the commands. The AGC module is configured to adjust the gain of the receiver and the slicer threshold voltage is updated when the notification is received from the command processor.
    Type: Grant
    Filed: June 4, 2012
    Date of Patent: April 7, 2015
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Andrew G. Zocher, Richard D. Davis, Theron L. Jones, Luiz A. Razera, Jr., Robert R. Rotzoll
  • Publication number: 20150094007
    Abstract: A radio receiver and method of operating the same are disclosed. In one embodiment, the radio receiver may include a RF receive path configured to convey a first radio signal within a first band to a radio tuning circuit. The RF receive path may be controllable using a first AGC circuit. The radio receiver may also include a loop-through path configured to convey a second radio signal within a second band between an input and an output of the radio receiver. The second band may be different from the first band. The loop-through path may be controllable using a second AGC circuit.
    Type: Application
    Filed: September 27, 2013
    Publication date: April 2, 2015
    Applicant: SILICON LABORATORIES INC.
    Inventors: Dan B. Kasha, Russell Croman, Mike R. May, Mark W. May, Navin Harwalkar, Tim Stroud
  • Patent number: 8983411
    Abstract: A method to control adjustable power levels uses a network of attenuators that includes a fixed attenuation and a variable attenuation. The method adjusts the variable attenuation to approach the fixed attenuation, provides gain to an attenuated signal in an amount proximate to the fixed attenuation to generate a compensated signal, and compares power levels of a non-attenuated signal and the compensated signal to generate a first error signal. The method introduces the fixed attenuation and correspondingly reduces the variable attenuation to maintain a combined attenuation. The combined attenuation generates a modified compensated signal. The method measures a difference between the first power levels of the non-attenuated signal and the modified compensated signal to generate a second error signal, and generates a control signal as function of the first and second error signals to adjust the variable attenuation to reduce an attenuation mismatch introduced between the fixed and variable attenuations.
    Type: Grant
    Filed: May 6, 2014
    Date of Patent: March 17, 2015
    Assignee: Skyworks Solutions, Inc.
    Inventors: Dmitriy Rozenblit, Darioush Agahi
  • Patent number: 8965317
    Abstract: Embodiments of the present invention may provide a signal processor with a wide gain range. The signal processor may comprise at least a discrete step gain stage and a continuous variable gain amplifier (VGA) stage. The discrete step gain stage may comprise a programmable gain amplifier (PGA) (e.g., low noise amplifiers 1 and 2 (LNA1 and LNA2)). The VGA stage may provide a continuous range to compensate the LNAs gain steps. In one embodiment, the AGC controller enables an inherent hysteresis with the AGC step change if required.
    Type: Grant
    Filed: April 26, 2011
    Date of Patent: February 24, 2015
    Assignee: Analog Devices, Inc.
    Inventors: Reza Alavi, Saeed Aghtar, Christoph Steinbrecher, Arathi Sundaresan
  • Patent number: 8948322
    Abstract: A system provides closed-loop gain control in a WCDMA mode and open loop control in an EDGE/GSM mode. Gain control is distributed across analog devices and a digital scaler in a wireless receiver. In the WCDMA mode, a loop filter generates an error signal that is forwarded to analog and digital control paths. The analog control path includes a first adder, a programmable hysteresis element, and a lookup table. The analog control signal is responsive to thresholds, which when used in conjunction with a previous gain value determine a new gain value. The digital control path includes a second adder, a programmable delay element, and a converter. A control word is responsive to a difference of the error signal, a calibration value, and the analog control signal. Blocker detection is provided in the WCDMA mode of operation. A controller sets system parameters using a state machine.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: February 3, 2015
    Assignee: Skyworks Solutions, Inc.
    Inventors: Jaleh Komaili, John E. Vasa, Thomas Obkircher
  • Patent number: 8923790
    Abstract: A wireless communication receiver includes a circuit, an analog-to-digital converter (ADC) and a processing circuit. The circuit receives a wireless signal and outputs an analog signal according to a gain index. The ADC converts the analog signal to a digital signal. The processing circuit adjusts the gain index according to a clipping number of the ADC.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: December 30, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chien-Wei Hsin, Chung-Yao Chang
  • Patent number: 8880012
    Abstract: A method (700) and apparatus (600) optimize resource block based transmitter operation in a wireless communication device. The method can include receiving (720) a radio resource assignment including a particular resource block allocation. The method can include configuring (730) a wireless communication transceiver for the particular resource block allocation. The method can include degrading (740) power amplifier distortion of the wireless communication transceiver based on the particular resource block allocation. The power amplifier distortion can be a measure of a deviation of the power amplifier output in an analysis domain from an ideal linear amplifier.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: November 4, 2014
    Assignee: Motorola Mobility LLC
    Inventors: Ryan J. Goedken, Armin W. Klomsdorf, Thomas D. Nagode, Dale G. Schwent
  • Patent number: 8880018
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: November 4, 2014
    Assignee: Silicon Laboratories Inc
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 8824361
    Abstract: A multi-frequency band receiver includes first and second receive paths, a combiner, a code multiplex baseband stage and an amplifier controller. The first and second receive paths receive and process first and second code multiplex signals, respectively. The first or the second receive path includes an amplifier having a variable gain factor. The combiner superposes the first and second processed code multiplex signals. The code multiplex baseband stage processes the superposed code multiplex signal to obtain and use first and second baseband receive signals. The first and second baseband receive signals represent data of the first and second code multiplex signals, respectively. In addition, the amplifier controller controls the gain factor of the amplifier having a variable gain factor so that the first or the second baseband receive signal includes a minimum reception quality which can be variably predetermined and is dependent on the operating state.
    Type: Grant
    Filed: July 23, 2012
    Date of Patent: September 2, 2014
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V.
    Inventors: Alexander Rügamer, Santiago Urquijo
  • Patent number: 8818299
    Abstract: Certain aspects and aspects of the present invention are directed to a distributed antenna system having a downlink communication path, an uplink communication path, and a non-duplexer isolator sub-system. The downlink communication path can communicatively couple a transmit antenna to a base station. The uplink communication path can communicatively couple a receive antenna to the base station. In one aspect, the non-duplexer isolator sub-system can be electronically configured for isolating uplink signals traversing the uplink communication path from downlink signals. In another aspect, a non-duplexer isolator sub-system can be configurable in one or more mechanical steps selecting a frequency response. In another aspect, a non-duplexer isolator sub-system can include an active mitigation sub-system.
    Type: Grant
    Filed: May 31, 2012
    Date of Patent: August 26, 2014
    Assignee: Andrew LLC
    Inventors: Charles B. Morrison, Donald R. McAllister, Fred W. Phillips, Christopher G. Ranson, Van E. Hanson, Thomas Kummetz, Gregory Allan Maca
  • Patent number: 8811537
    Abstract: Provided are a receiving apparatus and method for a wireless communication system using multiple antennas. A receiving method for a wireless communication system using multiple paths, the receiving method comprising: receiving signals through a predetermined number of multiple paths; sensing a carrier according to saturation state degrees of the signals, and providing saturation state information; calculating automatic gain components of the received signals by using the received signals and the saturation state information of the received signals; and performing a noise matching process to amplify noises on the predetermined multiple paths according to the automatic gain components during a predetermined period.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: August 19, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Il-Gu Lee, Jung-Bo Son, Je-Hun Lee, Eun-Young Choi, Sok-Kyu Lee
  • Patent number: 8805284
    Abstract: Interference in a wireless communication system receiver, such as at a base station, is identified based on monitoring automatic gain control (AGC) events. AGC statistics in combination with base band processing are used to identify the interference. Performance degradation is evaluated, and interference mitigation solutions are proposed based on the identified interference. Mitigation solutions include IRC, scheduling restrictions, and filter modifications including replacement of filters.
    Type: Grant
    Filed: February 24, 2011
    Date of Patent: August 12, 2014
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Alireza Nejatian, Krister Sundberg
  • Patent number: 8798567
    Abstract: Disclosed herein is a gain control circuit including: an amplifying section configured to amplify an input voltage in such a manner that amplitude of an output voltage at an output terminal is kept constant; an allowable voltage acquirer configured to acquire an allowable voltage of an apparatus connected to the output terminal; a voltage divider configured to divide the output voltage according to a ratio between a maximum voltage of the amplified input voltage and the allowable voltage; and an adjusting section configured to further amplify the amplified input voltage according to the ratio and supply a resulting voltage to the output terminal.
    Type: Grant
    Filed: May 2, 2013
    Date of Patent: August 5, 2014
    Assignee: Sony Corporation
    Inventors: Yusuke Yoneyama, Noboru Sasho, Takeo Tokunaga
  • Patent number: 8781426
    Abstract: Techniques for controlling operation of control loops in a receiver are described. The operation of at least one control loop is modified in conjunction with a change in operating state, which may correspond to a change in linearity state, gain state, operating frequency, antenna configuration, etc. A change in linearity state may occur when jammers are detected and may cause bias current of analog circuit blocks to be adjusted. The at least one control loop to be modified may include a DC loop, an AGC loop, etc. The operation of a control loop may be modified by disabling the control loop or changing its time constant prior to changing operating state, waiting a predetermined amount of time to allow the receiver to settle, and enabling the control loop or restoring its time constant after waiting the predetermined amount of time.
    Type: Grant
    Filed: November 16, 2006
    Date of Patent: July 15, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Steven C. Ciccarelli, Brian Banister, Brian George, Soon-Seng Lau, Prasad Gudem, Arun Raghupathy
  • Patent number: 8774750
    Abstract: In one embodiment, the present invention includes a method for receiving a radio frequency (RF) signal and mixing the RF signal with a master clock to obtain a mixed signal, cyclically rotating the mixed signal to each of N gain stages for at least one cycle of the master clock, and summing the outputs of the N gain stages to provide an output signal.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: July 8, 2014
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 8774738
    Abstract: Embodiments of the present disclosure provide systems and methods for estimating gain and phase error in a wireless transmitter. Embodiments of the present disclosure provide a gain and phase controller that uses a digital gain and phase estimator to jointly estimate both gain and phase. The forward and feedback signals of a wireless transmitter are digitized using analog to digital (ADC) converters. The digital signals are correlated with each other to dynamically extract gain and phase estimates of the loop. The gain and phase estimates are used to correct gain and phase errors in the wireless transmitter.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: July 8, 2014
    Assignee: Broadcom Corporation
    Inventors: Sriraman Dakshinamurthy, Mohamed Mostafa, Derek Shaeffer, Dennis Pu, Peter Capofreddi
  • Patent number: 8768281
    Abstract: In one embodiment, the present invention includes a method for receiving a radio frequency (RF) signal and mixing the RF signal with a master clock to obtain a mixed signal, cyclically rotating the mixed signal to each of N gain stages for at least one cycle of the master clock, and summing the outputs of the N gain stages to provide an output signal.
    Type: Grant
    Filed: September 6, 2013
    Date of Patent: July 1, 2014
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 8731500
    Abstract: A gain control circuit adjusts the signal level of a received signal responsive to the bandwidth a received signal and/or the delay spread of the channel in which the signal has propagated. The bandwidth and delay spread are evaluated to estimate the amount of signal variation that is expected due to fast fading. Adjustments to the signal level are then made to avoid clipping while at the same time ensuring that the dynamic range of a receiver component is efficiently utilized.
    Type: Grant
    Filed: January 29, 2009
    Date of Patent: May 20, 2014
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventors: Leif Wilhelmsson, Jan Celander, Lars Sundström
  • Patent number: 8725099
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Grant
    Filed: October 30, 2012
    Date of Patent: May 13, 2014
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 8649751
    Abstract: Disclosed herein is a receiver, including: an amplifier for amplifying a received signal; a strain compensator for having a function of compensating for a strain generated in an output signal from the amplifier in accordance with a stain compensation amount which is controlled based on a bias signal from the output signal from the amplifier; and a stain compensation amount controlling portion for generating the bias signal and outputting the bias signal to the strain compensator so that the strain compensation is carried out with a compensation amount corresponding to a strength of the received signal.
    Type: Grant
    Filed: May 18, 2010
    Date of Patent: February 11, 2014
    Assignee: Sony Corporation
    Inventor: Naoto Yoshikawa
  • Patent number: 8626098
    Abstract: A transconductance comparator includes a comparator having an output of a detector configured to sense an amplitude of an output of a Variable Gain Amplifier (VGA) of a receiver as a first input and a reference amplitude level as a second input. The comparator generates an error signal based on the first input and the second input. The transconductance comparator also includes a transconductance amplifier having a differential voltage input based on the error signal generated through the comparator and generating an output current. The transconductance amplifier includes current sources associated with programmable current limits thereof and differential pairs associated with the current sources, one or more of which is implemented with a size mismatch between transistors thereof to eliminate an offset error due to a mismatch between the current limits, thereby enabling programmability of an attack time and a decay time during automatic gain control of the VGA.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: January 7, 2014
    Assignee: Tahoe RF Semiconductor, Inc.
    Inventor: Darrell Lee Livezey
  • Patent number: 8583064
    Abstract: A receiver includes a first mixer configured to provide an in-phase (I) component of a radio frequency (RF) signal to an I channel by down-converting the RF signal, a second mixer configured to provide a quadrature (Q) component of the RF signal to a Q channel by down-converting the RF signal, amplification means, arranged on the I and Q channels, configured to amplify the I and Q components, a mismatch estimator configured to convert the amplified I and Q components into a frequency domain, and estimate a gain mismatch value and a phase mismatch value on the basis of the converted components, and a mismatch compensator configured to compensate for mismatch of the received signal on the basis of the estimated gain and phase mismatch values.
    Type: Grant
    Filed: October 13, 2011
    Date of Patent: November 12, 2013
    Assignee: GCT semiconductor, Inc.
    Inventors: Young Hwan Kang, Jiyoung Cho, Suwon Kang
  • Patent number: 8577319
    Abstract: An automatic gain control loop disposed in a receiver is adapted to compensate for varying levels of out of band interference sources by adaptively controlling the gain distribution throughout the receive signal path. One or more intermediate received signal strength indicator (RSSI) detectors are used to determine a corresponding intermediate signal level. The output of each RSSI detector is coupled to an associated comparator that compares the intermediate RSSI value against a corresponding threshold. The take over point (TOP) for gain stages is adjusted based in part on the comparator output values. The TOP for each of a plurality of gain stages may be adjusted in discrete steps or continuously.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: November 5, 2013
    Assignee: MaxLinear, Inc.
    Inventors: Curtis Ling, Madhukar Reddy, John Wetherell
  • Patent number: 8571152
    Abstract: The present invention discloses an apparatus and method for power-saving switch on a pair of configurable analog-to-digital converters. The apparatus mainly comprises an antenna, an antenna switch, a zero-IF RF receiver, and a baseband demodulator. By using a first and a second control signal to control the ON/OFF states of a plurality of switches and a plurality of stage units in the configurable analog-to-digital converters, and the third control signal to control the ON/OFF states of a plurality of LNA stages and the gain of a plurality VGAs, the power saving of the analog-to-digital converter is easily achieved.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: October 29, 2013
    Assignee: ISSC Technologies Corp.
    Inventors: Jeng-Hong Chen, Chin-Chang Chang, Kuang-Hu Huang, Chih-Ching Huang, Che-Kang Sun, Chun-Yuan Huang
  • Patent number: 8559903
    Abstract: An automatic gain control circuit is provided for an input signal in the form of a dc reference level and a superposed amplitude modulated ac data signal. A feedforward AGC loop has a low pass filter for deriving the level of attenuation from the attenuated dc reference level. A multiplier value (G) is based on the reciprocal of the level of attenuation (?) and this multiplier enables an output signal to be generated comprising a constant multiple (DG) of the input signal.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: October 15, 2013
    Assignee: NXP B.V.
    Inventors: Henk Ten Pierick, Gertjan Groot Hulze, Erik Keukens
  • Patent number: 8543077
    Abstract: In one embodiment, the present invention includes a method for receiving a radio frequency (RF) signal and mixing the RF signal with a master clock to obtain a mixed signal, cyclically rotating the mixed signal to each of N gain stages for at least one cycle of the master clock, and summing the outputs of the N gain stages to provide an output signal.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: September 24, 2013
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 8538363
    Abstract: The first control circuit controls the gain of the variable gain amplifier circuit and the cut-off frequency of the first low-pass filter so as to keep constant a product of a transfer function of the variable gain amplifier circuit and a transfer function of the first low-pass filter. The second control circuit compares a level of the second feedback signal and a preset threshold value after completion of gain control of the variable gain amplifier circuit, the second control circuit inputting the signal outputted from the first low-pass filter, as the first feedback signal to the first terminal as long as the level of the second feedback signal is not lower than the threshold value, the second control circuit inputting the signal outputted from the second low-pass filter, as the first feedback signal to the first terminal.
    Type: Grant
    Filed: March 19, 2012
    Date of Patent: September 17, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Daisuke Miyashita
  • Patent number: 8538366
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Grant
    Filed: October 31, 2011
    Date of Patent: September 17, 2013
    Assignee: Silicon Laboratories Inc
    Inventor: Aslamali A. Rafi
  • Patent number: 8532168
    Abstract: A receiver includes an adaptive equalizer, a power detecting unit and an adjusting unit. The adaptive equalizer is for receiving a signal and generating an equalized signal. The power detecting unit, coupled to the adaptive equalizer, is for detecting the strength of the equalized signal during a first period to generate a first strength signal, and detecting the strength of the equalized signal during a second period to generate a second strength signal. The adjusting unit, coupled to the power detecting unit and the adaptive equalizer, is for adjusting the compensation strength for the adaptive equalizer according to the first and second strength signals.
    Type: Grant
    Filed: April 29, 2010
    Date of Patent: September 10, 2013
    Assignee: Mstar Semiconductor, Inc.
    Inventors: Po Nien Lin, Sterling Smith
  • Patent number: 8521198
    Abstract: Techniques for operating a receiver to linearity performance and higher receive signal to noise ratio are described. The receiver includes one or more circuit blocks, e.g., a low noise amplifier (LNA), having discrete gain states. The gain states are selected based on switch points, with each switch point indicating a specific received signal level at which to switch from one gain state to another gain state. The switch points may be dynamically selected based on channel conditions, which may be characterized by the presence or absence or strength or frequency of jammers. A first set of switch points may be selected when jammers are detected, and a second set of switch points may be selected when jammers are not detected. The gain states are selected in accordance with the set of switch points selected for use.
    Type: Grant
    Filed: November 16, 2006
    Date of Patent: August 27, 2013
    Assignee: QUALCOMM, Incorporated
    Inventors: Steven C. Ciccarelli, Brian George, Soon-Seng Lau
  • Patent number: 8521114
    Abstract: Automatic Gain Control AGC circuit comprising a PIN-diode attenuator having an input and an output and a control circuit connected to the attenuator so as to read a signal at the attenuator output. The control circuit is configured to supply a feedback control signal to the attenuator based on an error signal between the signal read at the attenuator output and a reference signal, so as to modulate an attenuation level of said attenuator and maintain a substantially constant power level at the attenuator output. The control circuit particularly comprises at least a resistor and a capacitor which define a time constant of the AGC circuit, so that the AGC circuit features a main pole depending on such time constant and on a voltage of the feedback control signal. The control circuit also comprises a variable gain block, which receives the feedback control signal and which is configured to modulate the main pole proportionally to a variable gain (G) of the gain block.
    Type: Grant
    Filed: February 22, 2008
    Date of Patent: August 27, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Antonio Carugati
  • Patent number: 8514771
    Abstract: A wireless terminal determines the transmission power used for its dedicated control channel at a point in time, and generates a power report indicating a ratio of a maximum wireless terminal transmit power to the transmit power of the dedicated control channel at the point in time. The power report provides a measure of available transmit power for wireless terminal use for other purposes, e.g., uplink traffic channels, after taking into consideration the transmit power used for the dedicated control channel. The point in time has a known time offset from the start of a communications segment in which the power report is transmitted. This allows the base station receiving dedicated control channel uplink signals from the wireless terminal to measure the received signals, receive and process the communicated power report, and correlate information to be used for accurate wireless terminal closed loop power control.
    Type: Grant
    Filed: January 17, 2006
    Date of Patent: August 20, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Arnab Das, Sundeep Rangan
  • Patent number: 8514991
    Abstract: Disclosed is a radio frequency (RF) receiver for receiving a communication channel modulated on one or more carrier frequencies. The receiver may include a gain adjustable RF amplifier, a wideband signal power measurement circuit, and control logic. The control logic may be adapted to use outputs of one or more measurement circuits to classify interfering signals based on measured signal power and spectral proximity to the one or more channel carrier frequencies, and to adjust the gain of the radio frequency amplifier based on the classification.
    Type: Grant
    Filed: June 7, 2012
    Date of Patent: August 20, 2013
    Assignee: Siano Mobile Silicon Ltd.
    Inventors: Roy Oren, Noam Lavi
  • Patent number: 8509290
    Abstract: A closed loop power output calibration system for variable power output wireless devices. The wireless device includes a wireless transceiver having a transmit core coupled to a discrete power amplifier. Power detection circuitry formed in the wireless transceiver provides a detected power level of the power amplifier, and a reference power level, both of which are converted to digital signals using existing I and Q signal analog to digital converters in the receiver core. The digital signals are processed to cancel power distortion and temperature effects to provide a resulting power feedback signal. Corrective control signals are generated in response to the power feedback signal relative to a desired power output level. The gain in the transmit core is then adjusted in response to the corrective control signals such that the power amplifier outputs the target output power level.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: August 13, 2013
    Assignee: Icera Canada ULC
    Inventors: Abdellatif Bellaouar, Tajinder Manku
  • Patent number: 8498366
    Abstract: A system and technique for providing to flexible, programmable frequency estimators and spectrum analyzers that can operate over extremely large bandwidths and yet provide high spectral resolution are described. The system and technique may include a cascaded super-heterodyne apparatus for estimating a frequency and a bandwidth of signals proximate in frequency to a desired signal, a tunable filter coupled to an input of a receiver, and a tuner which receives a signal from said cascaded super-heterodyne apparatus and tunes the filter to filter out unwanted signals from the receiver.
    Type: Grant
    Filed: January 18, 2012
    Date of Patent: July 30, 2013
    Assignee: Massachusetts Institute of Technology
    Inventors: Soumyajit Mandal, Serhii M. Zhak, Rahul Sarpeshkar
  • Patent number: 8493954
    Abstract: A method and an apparatus for reducing Digital-to-Analog Conversion (DAC) bits at a transmitter of a Frequency Division Multiple Access (FDMA) system reduces a number of the bits for conversion so as to save power and reduce the cost of operation. The method can include generating a digital signal gain control value and an analog signal gain control value using subcarrier allocation information, a required Signal to Noise Ratio (SNR), and a Peak to Average Power Ratio (PAPR); controlling a gain of a signal input to a digital-to-analog converter using the digital signal gain control value; converting a digital signal of the controlled gain to an analog signal using the digital-to-analog converter; and restoring an original signal by controlling a gain of a signal output from the digital-to-analog converter using the analog signal gain control value.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: July 23, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jun-Kyu Kang, In-Tae Kang, Jeong-Gil Lee, Bo-Rham Lee, Sang-Min Bae
  • Patent number: 8463225
    Abstract: The present invention is provided to shorten the period of DC offset cancellation operation. One of terminals of two calibration resistors is connected to the differential output terminals of an active low pass filter having a filter process and an amplification function, and two input terminals of a voltage comparator and two terminals of a switch are connected to the other terminal of the two calibration resistors. In a calculation period of calculating digital control signals for reducing DC offset voltage, the voltage comparator detects calibration voltage depending on a voltage drop of one of the calibration resistors caused by analog current of a digital-to-analog converter. In a calibration period of reducing the DC offset voltage, the calibration analog current of the digital-to-analog converter responding to the digital control signal is passed to the input side of the filter via the switch.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: June 11, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Yutaka Igarashi, Yusaku Katsube
  • Patent number: 8442466
    Abstract: A frequency modulation (FM) transmitter implemented with a delta-sigma modulator and a phase-locked loop (PLL) is described. The delta-sigma modulator receives a modulating signal (e.g., an FM stereo multiplex (MPX) signal) and provides a modulator output signal. The PLL performs frequency modulation based on the modulator output signal and provides an FM signal. The FM transmitter may further include a gain/phase compensation unit and a scaling unit. The compensation unit may compensate the modulating signal for the closed-loop response of the PLL. The scaling unit may scale the amplitude of the modulating signal based on a gain to obtain a target frequency deviation for the FM signal. The PLL may operate in a transmit mode or a receive mode, may perform frequency modulation in the transmit mode, and may provide a local oscillator (LO) signal at a fixed frequency in the receive mode.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: May 14, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Pushp Trikha, Tzu-wang Pan, Eugene Yang, Yi Zeng, I-Hsiang Lin, Tg Vishwanath
  • Patent number: 8437720
    Abstract: An apparatus and method is disclosed for adjusting a gain of an amplifier assembly array. The amplifier assembly array includes a first stage to provide an amplified signal based upon an input signal. The first stage has a variable gain controlled in response to one or more gain control signals. An Automatic Gain Control (AGC) module generates the one or more gain control signals according to a ramp function in response to a power level of the amplified signal. The first stage may include a first low noise amplifier (LNA) to amplify the input signal to provide a first amplified input signal and a second LNA to amplify a second input signal to provide a second amplified signal. A switch selects between the amplified signal and the second amplified signal to provide the amplified signal. The amplifier assembly array may additionally include a second stage to provide a second amplified signal based upon the amplified signal.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: May 7, 2013
    Assignee: Broadcom Corporation
    Inventors: Lawrence M. Burns, Charles Brooks, Leonard Dauphinee